package com.example.text.quote;

import io.netty.bootstrap.Bootstrap;
  import io.netty.buffer.Unpooled;
  import io.netty.channel.Channel;
  import io.netty.channel.ChannelOption;
  import io.netty.channel.EventLoopGroup;
  import io.netty.channel.nio.NioEventLoopGroup;
  import io.netty.channel.socket.DatagramPacket;
  import io.netty.channel.socket.nio.NioDatagramChannel;
  import io.netty.util.CharsetUtil;
  
  import java.net.InetSocketAddress;
  
  /**
   * A UDP broadcast client that asks for a quote of the moment (QOTM) to {@link QuoteOfTheMomentServer}.
   *
   * Inspired by <a href="http://docs.oracle.com/javase/tutorial/networking/datagrams/clientServer.html">the official
   * Java tutorial</a>.
   */
  public final class QuoteOfTheMomentClient {
  
      static final int PORT = Integer.parseInt(System.getProperty("port", "7686"));
  
      public static void main(String[] args) throws Exception {
  
          EventLoopGroup group = new NioEventLoopGroup();
          try {
              Bootstrap b = new Bootstrap();
              b.group(group)
               .channel(NioDatagramChannel.class)
               .option(ChannelOption.SO_BROADCAST, true)
               .handler(new QuoteOfTheMomentClientHandler());
  
              Channel ch = b.bind(0).sync().channel();
  
              // Broadcast the QOTM request to port 8080.
              ch.writeAndFlush(new DatagramPacket(
                      Unpooled.copiedBuffer("QOTM?", CharsetUtil.UTF_8),
                      new InetSocketAddress("255.255.255.255", PORT))).sync();
  
              // QuoteOfTheMomentClientHandler will close the DatagramChannel when a
              // response is received.  If the channel is not closed within 5 seconds,
              // print an error message and quit.
              if (!ch.closeFuture().await(5000)) {
                  System.err.println("QOTM request timed out.");
              }
          } finally {
              group.shutdownGracefully();
          }
      }
  }
